[sidewayzisbest]

Ill go ahead and state i dont know much about home hvac

Im in the process of a big remodel on a older home. And I believe its called the cold air return vent. Its a 20x25 vent in the hallway. I am wanting to do a couple of things to it. First off i was going to go with a wooden cover to update it (http://www.woodreturnairgrills.com/) cheapest place i found them about 100 bucks for a 20x25 if anyone is looking also.


But anyways i can tell they did a horrible job they use to have a really small one (crappy patch up job too and then moved the 20x25 higher on the wall) and its vented just into a enclosed wall about 4'x2'. The sheetmetal comes to the subfloor then its just open space to the filter. I pulled the next wall wood panel down to drywall it and i prob shop vac 4lbs of dust/dirt from that area. So i would like to put a sheetmetal box from the floor to the vent to keep it enclosed.

Whats the best way to do this what size sheetmetal, hardware to use rivet/screws or even weld, kind of caulk. I want to do this the right way.

Also since they changed the size of it how do i know thats the right size is bigger always better? I would like to do a slimmer one but i dont want to cut air flow.

 

[beenthere]

First.You need to determine how much air it is suppose to be moving.
Then determine how much bigger the new wood return grille needs to be.

Or what the PD across it will be. Then you can determine better what size teh duct needs to be.

 

[sidewayzisbest]

how do i find that out

heres a pic of the plate on the a/c

 

[beenthere]

The 024 in the model nuber indicates its a 2 ton unit.
So roughly 800 CFM of air.

 

[sidewayzisbest]

I think im going to stay at 20x25 for now reading thru some things since this is a old a/c if i ever upgrade i prob will need a 3 ton . I have roughly 1300sq ft on the first floor. Then im putting a windowless a/c in the frog so i think the 20x25 will cover either. It says it has 52% clear area....about 12% less then the metal units. Now i just got figure out the best way to get it enclosed.

thanks for the help

 

[beenthere]

And 3M tells people that their air filter last for 90 days.